Stem cells can be transformed into the pancreatic cells needed to treat diabetes and into complex layers of intestinal tissue, scientists demonstrated in two experiments reported on Sunday. In one, a team turned immature sperm cells into...

WASHINGTON — Stem cell researchers have found a way to turn a person’s skin into blood, a process that could be used to treat cancer and other ailments, according to a Canadian study published Sunday. The method uses cells from a patch of...